Public health workers from nearly a score of countries gathered in Cambodia to play a game - a game they hope will help make Southeast Asia better able to handle pandemic disease.

In this game, the goal is to manage a severe pandemic that breaks out in a fictional region - known as Pandemica - that is comprised of six countries.

The players - public health workers from the Association of Southeast Asian Nations, the United Nations, the European Union, the United States and other countries - are deadly serious about this game.

At the start of the five-day exercise this week in Phnom Penh, ASEAN Secretary-General Surin Pitsuwan said the attendees will be able to learn best practices from each other. And, he said, just as importantly, they will get to know their counterparts in other countries.

"I think a closer network of not only health workers, but all sectors in the national preparedness for such a catastrophe will be a most practical outcome. That is they know each other, they know each other's numbers, they know each other's addresses, and they will continue to inform each other what situation is occurring in their particular member state so that a quick collective action can be taken as an organization," he said.

Surin added that challenges such as pandemics, financial crises and climate change are too big for individual countries to deal with, and require regional or even global responses.

Within nations, he says, combating a pandemic requires a "whole of society" approach extending beyond the health sector to include those who provide food, utilities, public security and transportation.

And he warned that failure to respond appropriately could lead to severe social and economic disruption.

"If we are not careful it will certainly undermine our own economic growth and our own resilience in the region," he said. "It's natural that all these countries should come together and make sure that each will not be affected more severely, and no-one wants to be that weak link in the chain of defense."

Surin says the world escaped relatively lightly with the 2003 SARS outbreak. Then, a new virus appeared in southern China and quickly spread around the world. Thousands were hospitalized with severe pneumonia and more than 800 people died before strict quarantine measures in several countries brought it under control.

The outcome of this week's exercise, he says, ought to be a region that can deal with the worst-case pandemic scenarios with a minimum of losses, and help the rest of the world learn the right lessons, too.